This art history video discussion examines Gerard David's "The Virgin and Child with Saints and Donor", c. 1510, oil on oak, 105.80 x 144.40 cm (The National Gallery, London).

This art history video dicussion examines Willem de Kooning's "Woman I", oil on canvas, 1950-52 (MoMA).

This art history video discussion examines Piet Mondrian's "Composition No. II, with Red and Blue", oil on canvas, 1929 (original date partly obliterated; mistakenly repainted 1925 by Mondrian). Oil on canvas, 15 7/8 x 12 5/8" (40.3 x 32.1 cm) (The Museum of Modern Art).

Sal discusses the conditions of matrix dimensions for which addition or multiplication are defined. Created by Sal Khan.

This art history video discussion examines Edgar Degas' "The Bellelli Family", 1858-67, oil on canvas (Musee d'Orsay, Paris). Degas was in his mid-twenties when he painted this canvas. It depicts from left to right, the ten-year-old Giovanna, her mother, the artist's paternal aunt Laura, her younger daughter, Giula age 7, and the Baron Gennaro Bellelli. Preperatory sketches for the painting may have been made in Florence where the family was living, the Baron had been exiled from Naples. The picture may have been completed in Paris.

This art history video discussion examines Edgar Degas' "The Dance Class" oil on canvas, 1874 (Metropolitan Museum of Art).

This art history video discussion examines Edgar Degas' "At the Races in the Countryside", 1869, oil on canvas, 36.5 x 55.9 cm / 14-3/8 x 22 inches (Museum of Fine Arts, Boston).

This art history video discussion examines Edgar Degas', "Visit to a Museum", c. 1879--90, oil on canvas, 91.8 x 68 cm / 36-1/8 x 26-3/4 inches (Museum of Fine Arts, Boston).

This art history video discussion examines Eugene Delacroix's "Scene of the Massacre at Chios": Greek families awaiting death or slavery, 1824 Salon, oil on canvas, 164" x 139" (419 cm x 354 cm) (Musee du Louvre, Paris) .

This art history video discussion examines Eugene Delacroix's "The Death of Sardanapalus", 1827, oil on canvas (Musee du Louvre, Paris).

Sociology often looks at different age cohorts. A cohort is simply a group of people, but here we're looking specifically at different age groups or generations, because these people all lived through the same certain events through a certain time that affected their lives similarly.

This lesson compares rational number and orders them from least to greatest using the number line. [Developmental Math playlist: Lesson 132 of 196]

This lesson demonstrates how to compare whole numbers. [Developmental Math playlist: Lesson 7 of 196]

This 10-minute video lesson provides an introduction to 2nd order, linear, homogeneous differential equations with constant coefficients. [Differential Equations playlist: Lesson 13 of 45]

This 8-minute video lesson continues the discussion from the previous video and shows how to find the general solution. [Differential Equations playlist: Lesson 14 of 45]

This 6-minute video lesson continues the discussion from the previous videos and introduces some initial conditions to solve for the particular solution. [Differential Equations playlist: Lesson 15 of 45]

This 9-minute video lesson continues the discussion from the previous videos and provides another example using initial conditions. [Differential Equations playlist: Lesson 16 of 45]

This 10-minute video lesson looks at what happens when the characteristic equations has complex roots. [Differential Equations playlist: Lesson 17 of 45]

This 10-minute video lesson continues the discussion of what happens when the characteristic equation has complex roots. [Differential Equations playlist: Lesson 18 of 45]

This 10-minute video lesson concludes the series on complex roots of characteristic equations and demonstrates an example with initial conditions. [Differential Equations playlist: Lesson 19 of 45]